Positron Emission Tomography in Predicting Response in Patients Who Are Undergoing Treatment With Pemetrexed Disodium and Cisplatin With or Without Surgery for Stage I, Stage II, or Stage III Non-Small Cell Lung Cancer

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed non-small cell lung cancer (NSCLC) Stage IB, II, IIIA, or IIIB (T4, N0-1) disease Staging must have been performed 4 weeks prior to study entry with a CT scan of chest, upper abdomen, and fludeoxyglucose F 18 (^18FDG) positron emission tomography (PET) scan Mediastinal evaluation and staging based on combination of CT scan and FDG-PET results If N1 or N2 nodes are found by FDG-PET or CT scan, metastases must be ruled out by brain MRI Measurable and resectable disease T4 lesions must be resectable Eligible for curative surgery No malignant pleural effusion PATIENT CHARACTERISTICS: Age 18 and over Performance status ECOG 0-1 Life expectancy Not specified Hematopoietic Absolute neutrophil count ≥ 1,250/mm^3 Platelet count ≥ 100,000/mm^3 Hepatic Bilirubin ≤ 1.5 times upper limit of normal (ULN) AST and ALT ≤ 3.0 times ULN Renal Creatinine clearance ≥ 45 mL/min Pulmonary Adequate pulmonary reserve to undergo surgery Predicted FEV_1 > 0.8 L after resection Other Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for 3 months after completion of study treatment Able to take corticosteroids Able to take folic acid or vitamin B_12 supplements No other malignancy within the past 5 years except nonmelanoma skin cancer or noninvasive cervical cancer No concurrent serious or uncontrolled disorder that would preclude study participation No type I diabetes mellitus Type II diabetes mellitus allowed if glucose is 80-150 mg/dL PRIOR CONCURRENT THERAPY: Biologic therapy No concurrent immunotherapy No concurrent prophylactic filgrastim (G-CSF) No concurrent thrombopoiesis-stimulating agents Chemotherapy At least 5 years since prior chemotherapy Endocrine therapy No concurrent anticancer hormonal therapy Radiotherapy No prior radiotherapy to the chest No concurrent curative or palliative radiotherapy Surgery Not specified Other At least 30 days since prior non-FDA-approved or investigational agents At least 5 days since prior aspirin or other nonsteroidal anti-inflammatory agents (8 days for long-acting agents [e.g., piroxicam]) No other concurrent anticancer therapy No other concurrent investigational agents